#ifndef MAGIC_EXPR_H_
#define MAGIC_EXPR_H_
#include "magic-interpreter.h"
#include "magic-interpreter-aux.h"

#ifndef MAX
#  define MAX(x,y) (((x)>(y)) ? (x) : (y))
#endif
#ifndef MIN
#  define MIN(x,y) (((x)<(y)) ? (x) : (y))
#endif

#ifndef INT_MAX
#  define INT_MAX (1<<30) // It's more than that, but this is quite sufficient for our purposes.
#endif

/*
 * Argument types:
 *  i : int
 *  d : dir
 *  s : string
 *  e : entity
 *  l : location
 *  a : area
 *  S : spell
 *  I : invocation
 *  . : any, except for fail/undef
 *  _ : any, including fail, but not undef
 */
typedef struct fun {
        char *name;
        char *signature;
        char ret_ty;
        int (*fun)(env_t *env, int args_nr, val_t *result, val_t *args);
} fun_t;

typedef struct op {
        char *name;
        char *signature;
        int (*op)(env_t *env, int args_nr, val_t *args);
} op_t;

/**
 * Retrieves a function by name
 * @param name The name to look up
 * @return A function of that name, or NULL, and a function index
 */
fun_t *
magic_get_fun(char *name, int *index);

/**
 * Retrieves an operation by name
 * @param name The name to look up
 * @return An operation of that name, or NULL, and a function index
 */
op_t *
magic_get_op(char *name, int *index);

/**
 * Evaluates an expression and stores the result in `dest'
 */
void
magic_eval(env_t *env, val_t *dest, expr_t *expr);

/**
 * Evaluates an expression and coerces the result into an integer
 */
int
magic_eval_int(env_t *env, expr_t *expr);

/**
 * Evaluates an expression and coerces the result into a string
 */
char *
magic_eval_str(env_t *env, expr_t *expr);

int
map_is_solid(int m, int x, int y);

expr_t *
magic_new_expr(int ty);

void
magic_clear_var(val_t *v);

void
magic_copy_var(val_t *dest, val_t *src);

void
magic_random_location(location_t *dest, area_t *area);

int // ret -1: not a string, ret 1: no such item, ret 0: OK
magic_find_item(val_t *args, int index, struct item *item, int *stackable);

#define GET_ARG_ITEM(index, dest, stackable) switch(magic_find_item(args, index, &dest, &stackable)) { case -1 : return 1; case 1 : return 0; }

int
magic_location_in_area(int m, int x, int y, area_t *area);

#endif /* !defined(MAGIC_EXPR_H_) */
